Bug: Don't change to the default theme!

Just messing around with the settings, I thought I’d look at the other (default) theme available in Preferences: Interface, with every intention of changing it back. Only changing it back wasn’t so simple! A huge Patreon logo appeared over the controls, making them unusable! This on the latest Firefox.
It only seems to be recoverable by using web developer tools to select the div with the logo in it and delete it from the loaded page.

(Hoping this goes into the right place!)

Lol its our way to punish you for using another theme and say GIVE US YOUR MONEY!

Being serious now that is because the CSS for it is not in that theme. I will disable selecting it for now, but might re-enable it later once I have time to move the CSS over. Thanks for the heads up!